#include <stdio.h>
int main(int argc,char *argv[])
{
	double Sn=0;
	int n=1;
	int k;
	scanf("%d",&k);
	while(1)
	{
		Sn = Sn+1.0/n;
		n++;
		if(Sn>k)
		{
			break;
		}
	}
	printf("%d\n",n-1);
	return 0;
}
